co-worker crush! has he lost interest?

my co-worker and I are both new hires. We both started about a month and half ago.

We used to sit next to each other, then we got moved to a different location and we don’t sit together anymore.

He was around me all the time until last week. He would come to my desk and pretend that we are working together. He would flirt with me and make eye contacts with me.He calls me nicknames and tease me a lot.

I think I have been giving him signs that i like him too. I make eye contacts with him and flirt with him. I touch his hand and shoulder some time. One day I asked him if he could take me to subway cuz i wasn’t sure where Q train station was. He said, he couldn’t because he had to work late. After that, he kinda waited one day until i leave work and tried to take the same elevator as me. but that was all.

I brought him muffins one day and he said no. When i offer mint, he takes it though. And he said no to the ointment i brought for his mosquito bites.

since last week, he stopped coming to my desk. and stopped being chatty like he used to. He leaves work earlier than before too.

He doesn’t seem like he has a gf but Im not sure and I don’t know how to find out. He seems very confident at work but im not sure how he is in relationship department. I’ve heard him complain once in a while saying oh this and that person likes you better than me. So i know he has that insecurity.

I just want to know if there is someone else in the picture or may be he wasn’t interested and it was all in my head?